In recent years, active matrix display devices are actively developed. According to the active matrix, a high-quality image display with few incidental images is realized by disposing an active element in each pixel. Furthermore, high-performance display devices with small external load are developed by incorporating driver circuits such as a shift register on an insulating substrate around pixels.
As for a display device having pixels arranged in a matrix, such problems as breaking and short-circuit of wirings are likely to occur in the manufacturing steps. Therefore, electrical inspections are frequently carried out during the manufacturing steps (see Patent Document 1).
[Patent Document 1]
Japanese Patent Laid-Open No. Hei 7-287247